Abstract: Metal-organic Frameworks MIL-53(Al) has been hydrothermally synthesized and investigated by means of X-ray diffraction (XRD) and N2 adsorption-desorption experiment. Adsorption isotherms of C8 aromatic isomers, including para-xylene, ortho-xylene, meta-xylene, and ethylbenzene, in metal-organic framework Mil-53(Al) has been systematically investigated by using intelligent gravimetric analyzer (IGA) at 303 K and 373 K. The results indicate that adsorption isotherms at 303 K present type-I isotherms. The deviation from normal Langmuir model of the isotherms at 373 K can be, however, found because of the breathing effect of Mil-53(Al) framework. The results also indicate that o-xylene in this material has very good adsorption capacity, while effect of ethylbenzene adsorption is the worst. Two-component mixture separation factor can be obtained through the fixed bed breakthrough experiments and gas chromatography analysis. It has good separation performance of o-xylene and ethylbenzene, and selectivity achieved to 9.2. 

Key words: MIL-53(Al), Xylene, Ethylbenzene, Adsorption, Separation factor

摘要： 采用水热法合成了金属－有机骨架材料ＭＩＬ－５３（Ａｌ）并用ＸＲＤ和氮气吸附脱附等进行了表征。利用智能重量分析仪（ＩＧＡ）测定了邻、间、对二甲苯和乙苯各同分异构体分别在３０３Ｋ和３７３Ｋ时在ＭＩＬ－５３（Ａｌ）上的吸附等温线。在３０３Ｋ时吸附等温线属于典型的Ｉ型吸附等温线。温度为３７３Ｋ时，骨架因为发生了“呼吸”作用而使等温线偏离了Ｌａｎｇｍｕｉｒ模型，出现阶梯状吸附。吸附等温线的测定表明了邻二甲苯在此材料上具有非常好的吸附能力，而乙苯的吸附效果最差。通过固定床穿透实验和气相色谱的分析得到了二元组分混合物的分离因数，其中邻二甲苯／乙苯取得了较好的分离效果，分离因数达到９.２

关键词: ＭＩＬ－５３（Ａｌ） , 二甲苯 , 乙苯 , 吸附 , 分离因素